Improvement in lifting-jacks



B. HARRISON.

, Lifting-lacks.

$10,154,245 P atented Aug. 1 8,1874

F ax

UNITED STATES PATENT QFFIOE.

BENJAMIN HARRISON, OF KINGSLAND, ENGLAND.

IMPROVEMENT IN LlFTlNG-JACKS.

Specification forming part of Letters Patent No. 154,246. dated August18, 1874 application filed July 6,1874.

jack upon strong wheels or rollers, the peripheries of which I serrateor cross-cut, to insure greater hold on the ground. These wheels orrollers are provided with axles which work in bearings in the lower partof the body of the jack, and on one of the axles of each of theserollers I fix a worm-wheel, into which gear worms carried on ahorizontal shaft which may be actuated by means of a ratchet-lever orotherwise. By turning this shaft in one direction or the other the jackmay be traversed to any I desired distance, whileat the same time it maybe employed as a stationary lifting-jack, the rollers remaining fixed,unless actuated as above described. The eleyating portion of the jackmay be worked by any suitable or wellknown arrangement of mechanism, Alip or platform is formed on the lower end of the lifting portion,forthe purpose of enabling me to raise heavy weights from ofi theground. For this purposeI make the elevating screwor rack sufficientlylong to allow the lip before mentioned to descend below the ground,which would jbe cut away for that purpose. In order to prevent the jackfrom tilting when employ ing the lip for raising, I constructthelfollers in such a manner as that a portion thereof shall projectoutside the body of the jack on that side, from which the lip projects,so as to afford a more extended base. If desired, a steering apparatusmay be combined with the above so as to enable the jack to be traversedin any direction other than a straight line; and In orderthat my saidinvention maybe fully understood, I shall now proceed more particularlyto describe the same, and for that purpose shall refer to the severalfigures on the annexed sheet of drawings, the same letters of referenceindicating corresponding parts in all thefigures. Figure 1 represents afront elevation of my improved traveling jack; Fig. 2, a back elevation,and Fig. 3 an end elevation, of the same.

A represents the framing or body of the jack mounted upon rollers orwheels B B, the axles of which extend between and project at each oftheir ends beyond the front and rear sides, respectively, of the framingor body A, and are carried by bearings 1 2 3 4 formed on the under sideof the said framing or body, as shown. At one end of each of theseprojecting axles is fixed a worm-wheel, G, into which gears a worm, D,the two worms being fixed to or forming part of a horizontal shaft, E,mounted in bearings 5 6 on the side of the framing or body A, androtated in either direction and from either end by means of aratchet-lever, F, or by any other suitable contrivance. At the other oropposite projecting ends of the said axles .are supplementary oradditional rollers or wheels Gr G, which form anextended base to thejack, for the purpose hereafter described. The peripheries of therollers or wheels B B and those of the rollers G G are serrated orcross-cut to enable the said rollers to take a firmer bite or hold onthe ground when revolving. The bearing 1 of the axle to the roller orwheel B is capable of a horizontal movement or adjustment in the framingor body A, the said movement being radial to the opposite bearing 2, andeffected by means of a screw,

H,working through the bearing 1 and actuated by a ratchet-lever or othercontrivance, or the adjustment of the bearing 1 may be effected by anyother convenient method. I represents the elevating portion of the jack,which in this instance is a screw raised or lowered by the worm wheel ornut K bearing or resting on the top of the framing or body A,anda-worked by a worm, I1, as shown, but the said .elevating portion ofthe jack may consist in and be worked by arack-and-pinion gear or byhydraulic pressure, or by any other well-known arrangement of mechanism.The front side of the body or framing A is open or slotted to its bottomedge, as shown, so as to allow of the projecting foot M of the screw orelevating portion I of the jack to descend below the latter into theground, and thereby enable a low purchase to be taken at weights to beraised.

On lifting any weight in the ordinary manner by the projecting foot M ofthe elevating portion I the jack is preventedfrom tilting by thesupplementary or additional rollers or wheels G G, which form anextended base to the jack, as before mentioned, and on which, as well ason the main rollers or wheels B B,

- the whole apparatus takes its hearing as on the base of any ordinaryjack.

By turning the rollers or wheels B B, and

with them the supplementary or additional rollers or wheels G G, ineither direction, the jack can be movedor traveled endwise along theground accordinglyto any required distance and at the same operation,without the inconthe rollers or wheels G G may be made to be readilythrown in or out of gear with their wheels, so that the jack can bepushed along without their aid.

One special feature of my improvement consists in giving an increasedform and disposition of material to the lower portion of the framing orbody A, as shown, whereby a greater rigidity and strength in the jack isattained.

I claim- 1. The combination of a lifting-jack with the rollers B B, andworms and worm-wheels for operating and securing said rollers, asspecified.

2. The combination of the jack with its rollers B B and the adjustableroller-bearings l 2, as and for the purpose set forth.

In witness whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

BENJ. HARRISON.

Witnesses:

CHAS. MILLs,

47 I/incolns Inn Fields, London. EDWARD D. FARREL,

47 Lincolns Inn Fields, London.

